Benzyl Bromide → [[(2R,3R,4S,5R,6S)-3,4,5-tribenzyloxy-6-[4-chloro-3-[[4-(2,2,2-trifluoroethoxy)phen yl]methyl]phenyl]-6-methoxy-tetrahydropyran-2-yl]methoxy]tert-butyl-dimethyl-silane

Participants

Reaction Conditions

Reaction Steps

To a suspension of sodium hydride (1.90 g, 47.4 mmol, 60% dispersion in Mineral oil) in anhydrous tetrahydrofuran (50 mL) was added a solution of (2S,3R,4S,5S,6R)-6-[[tert-butyl (dimethyl)silyl]oxymethyl]-2-[4-chloro-3-[[4-(2,2,2-trifluoro ethoxy)phenyl]methyl]phenyl]-2-methoxy-tetrahy dropyran-3,4,5-triol 17f (4.8 g, 7.91 mmol) in anhydrous tetrahydrofuran (50 mL) slowly at 0° C. The mixture was stirred at 0° C. for 1 hour and warmed to room temperature. Then benzyl bromide (5.6 mL, 47.4 mmol) and tetrabutylammonium iodide (0.3 g, 0.79 mmol) were added in turn. The mixture was warmed up to 40° C. and further stirred for 12 hours. The reaction mixture was quenched with water (50 mL) and partitioned. The aqueous layer was extracted with ethyl acetate (50 mL×2). The combined organic layers were washed with saturated brine (80 mL), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated in vacuo and the residue was purified by silica gel chromatography eluted with PE/EtOAc(v/v)=20/1 to give the title compound 17g as orange-yellow oil (1.6 g, 23.0%). This material was not further purified.

Provenance & Evidence